正交频分复用无源时间反转信道均衡方法研究  

The study of orthogonal frequency division multiplexing passive time reversal channel equalization

作　　者：尹艳玲[1,2] 乔钢[1,2] 刘凇佐[1,2] 

机构地区：[1]哈尔滨工程大学水声技术重点实验室,哈尔滨150001 [2]哈尔滨工程大学水声工程学院,哈尔滨150001

出　　处：《声学学报》2015年第3期469-476,共8页Acta Acustica

基　　金：国家863计划(20099AA093601-2);水声技术重点实验室基金(9140C200801110C2004);国家自然科学基金(11274079)资助

摘　　要：针对水声信道多途信号引起的正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)水声通信系统符号间干扰的问题,提出了无源时间反转均衡的方法,将发送的探测信号时间反转与OFDM信号做卷积,利用无源时间反转镜的时间聚焦原理减小信道多途带来的符号间干扰,在OFDM符号中不使用导频的情况下实现信道均衡,简化了均衡步骤并提高了OFDM符号频带利用率。分析比较了无源时反均衡方法与最小平方信道均衡在水声多途信道下的误码性能。仿真研究和湖上实验表明,无源时反信道均衡算法可以有效的减小多途信道对OFDM水声通信系统带来的影响。To solve the problem of the Orthogonal Frequency Division Multiplexing （OFDM） inter-symbol interference caused by underwater acoustic multipath channels, a passive time reversal channel equalization scheme is proposed. Time reverse the probe signal and convolute it with the OFDM signals. The inter-symbol interference caused by multipath channels will be alleviated on the time focusing principle of passive time reversal mirror. There is no need for pilots to realize the channel equalization which simplifies the processing steps and enhances the bandwidth efficiency. The bit error rate performances are compared to the least square channel equalization. The simulation and lake experiments results show that the passive time reversal channel equalization can alleviate the influence on the OFDM underwater acoustic communication caused by the multipath channel effectively.

关 键 词：时间反转镜 正交频分复用 水声信道 均衡方法 无源 OFDM信号 Division 符号间干扰 

分 类 号：O427[理学—声学]